1. Field of the Invention
The present invention relates to a vehicle body reinforcement device for reinforcing a body when the device is mounted to the body such that two portions to be reinforced are connected to each other.
2. Description of the Related Art
Conventionally, a body of a motorcar has been formed such that a highest possible strength is effected while aiming at weight saving. In such bodies, a reinforcement member is mounted to a region where a greater strength is required compared with other regions, such as a section where a wheel suspension device is mounted. The reinforcement member is mounted in such a manner that two portions to be reinforced are connected to each other. As for such a reinforcement member, there has been known one formed in the shape of a rod by a rigid body or one in which damping force generating means is provided, for example, as shown in JP-A-2002-211437.
The reinforcement member disclosed in JP-A-2002-211437 is formed in an elongated shape and damping force generating means is provided in its middle in the longitudinal direction. The damping force generating means can be a hydraulic damper or a rubber member. This reinforcement member spans the space between two portions to be reinforced of a body. In one use, the reinforcement member can be mounted between a suspension mounting portion on the left side of the body and a suspension mounting portion on the right side thereof.
The body of an automobile is some times subjected to elastic deformation in a direction in which the distance between the two portions to be reinforced is shortened or lengthened, such as during quick handling operations. At this time, a load is also applied, in the direction of compression or the direction of elongation, to the reinforcement member connecting the portions to be reinforced to each other. If a reinforcement member formed only by a rigid body is used, the reinforcement member is subjected to elastic deformation in the direction of compression or the direction of elongation by the load applied to the body when it is deformed, as described above.
This reinforcement member stretches or contracts by its own elasticity when it is released from the load or when the force causing the elastic deformation vanishes. The conventional rigid reinforcement member begins to vibrate in the longitudinal direction due to loading during quick handling operations because of the member's longitudinal elongation and contraction. Therefore, while the vehicle body using this rigid reinforcement member is less likely to be elastically deformed, it may provide unnecessary vibration in the reinforcement member.
Such a disadvantage can be reduced by using a reinforcement member having damping force generating means such as disclosed in JP-A-2002-211437. This is because vibration of the reinforcement member itself is damped by the damping force generating means.
However, such damping reinforcement member has a decreased repulsion force under axial loading. Therefore, the ability to suppress deformation of the body is lower than that of a rigid reinforcement member.
In view of the foregoing, a body reinforcement device for a vehicle is desired that can reliably suppress deformation of a body and which reduces vibration in the reinforcement device as well.